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Interactive effects of reproductive assets and ambient predation risk on the threat-sensitive decisions of Trinidadian guppies

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Current Zoology 2016年第3期62卷 221-226页

作者： Jemma KATWAROO-ANDeRSeN Chris K. eLVIDGe Indar RAMNARINe Grant e. BROWN Department of Biology Concordia University 7141 Sherbrooke St. West Montreal QC H4B 1R6 Canada Department of Life Sciences University of the West Indies St. Augustine Trinidad and Tobago

Threat-sensitive behavioral trade-offs allow prey animals to balance the conflicting demands of successful predator detection and avoidance and a suite of fitness-related activities such as forag- ing, mating, and territorial defense. Here, we test the hypothesis that background predation level and reproductive status interact to determine the form and intensity of threat-sensitive behavioral decisions of wild-caught female Trinidadian guppies Poecilia reticulata. Gravid and nongravid gup- pies collected from high- and low-predation pressure populations were exposed to serial dilutions of conspecific chemical alarm cues. Our results demonstrate that there was ＇no effect of reproduct- ive status on the response of females originating from a low-predation population, with both gravid and nongravid guppies exhibiting strong anti-predator responses to the lowest concentration of alarm cues tested. Increasing cue concentrations did not result in increases in response intensity. Conversely, we found a significant effect of reproductive status among guppies from a high- predation population. Nongravid females from the high-predation population exhibited a strong graded （proportional） response to increasing concentrations of alarm cue. Gravid females from the same high-predation population, however, shifted to a nongraded response. Together, these re- sults demonstrate that accrued reproductive assets influence the threat-sensitive behavioral deci- sions of prey, but only under conditions of high-ambient predation risk.

关键词： asset protection antipredator behavior fitness trade-offs ecological uncertainty chemical alarm cues.

多元文化下的区域发展——中国西部民族区域发展研究

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广州大学学报（社会科学版） 2003年第1期2卷 53-56页

作者：吕拉昌广州大学地理系广东广州510405

中国是一个多民族的国家。各民族在长期适应地理环境的过程中形成了与汉族不完全相同的独特文化。由于文化背景不同 ,中国西部民族地区的发展模式不同于汉族和西方国家。结合知识文明与可持续发展状况 ,我国西部民族地区应寻求文化、生... 详细信息

中国是一个多民族的国家。各民族在长期适应地理环境的过程中形成了与汉族不完全相同的独特文化。由于文化背景不同 ,中国西部民族地区的发展模式不同于汉族和西方国家。结合知识文明与可持续发展状况 ,我国西部民族地区应寻求文化、生态、经济系统发展的模式 ,应从文化、经济、生态整合的角度 ,走以质取胜的道路。

关键词：西部民族地区多元文化经济文化生态整合发展

PUNTA DeLL'ORTO e COLMI:DeSCRIZIONe GeOLOGICA e NUOVe (?)(Prov. di Brescia)

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Natural Disaster Reduction in China 1981年第1期 185-190页

作者： MAUROCAVALLeRI ALBeRTODALOGLI ROSARIO NOVALI e PAOLO SeGALINI GruppoGrotte Brescia 《C.Allegretti》. GruppoGrotte Brescia 《C.Allegretti》. Centro Studi Naturalistici Bresciani. GruppoGrotte Brescia《C.Allegretti》

OSSeRVAZIONe GeOLOGICA DeLla ZONA Il massiccio carsico di 《Punta dell'Orto》è costituito da formazioni prevalente-mente calcaree di età mesozoica fra le quali hanno spiccato interesse speleogenetico la《Corna》 (Retico medio-Sinemuriano) e la 《Maiolica》 (Titoniano-Barremiano). Nella regione compresa tra Polaveno e Pilzone d'Iseo i rapporti fra le suddette for-mazioni sono caratterizzati da una notevole complessità strutturale, determinata dalsovrascorrimento in direzione SSW di un esteso piastrone di Coma sopra le più recenti

关键词： Long IV la di Brescia PUNTA DeLL’ORTO e COLMI Prov

Dissolved organic matter tracers reveal contrasting characteristics across high arsenic aquifers in Cambodia:A fluorescence spectroscopy study

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Geoscience Frontiers 2019年第5期10卷 1653-1667页

作者： laura A. Richards Dan J. lapworth Daniel Magnone Daren C. Gooddy Lee Chambers Peter J. Williams Bart e. van Dongen David A. Polya School of earth and environmental Sciences and Williamson Research Centre for Molecular environmental Science The University of ManchesterWilliamson BuildingOxford RoadManchesterM13 9PLUK British Geological Survey Maclean BuildingWallingfordOxfordshireOX10 8BBUK lancaster environment Centre Lancaster UniversityLancaster LA1 4YQUK Present address: School of Geography University of LincolnBrayford PoolLincolnLincolnshireLN6 7 TSUK Present address: Department of Civil and environmental engineering University of StrathclydeGlasgow G1 1XJUK

Organic matter in the environment is involved in many biogeochemical processes,including the mobilization of geogenic trace elements,such as arsenic,into *** this paper we present the use of fluorescence spectroscopy to characterize the dissolved organic matter (Dom) pool in heavily arsenicaffected groundwaters in Kandal Province,*** fluorescence Dom (fDom) characteristics between contrasting field areas of differing dominant lithologies were compared and linked to other hydrogeochemical parameters,including arsenic and dissolved methane as well as selected sedimentary ***-corrected fluorescence indices were used to characterize depth profiles and compare field *** fDom was generally dominated by terrestrial humic and fulvic-like components,with relatively small contributions from microbially-derived,tryptophan-like *** fDom from sand-dominated sequences typically contained lower tryptophan-like,lower fulvic-like and lower humic-like components,was less bioavailable,and had higher humification index than clay-dominated *** concentrations were strongly correlated with fDom bioavailability as well as with tryptophan-like components,suggesting that groundwater methane in these arsenic-prone aquifers is likely of biogenic origin.A comparison of fDom tracers with sedimentary om tracers is consistent with the hypothesis that external,surface-derived contributions to the aqueous Dom pool are an important control on groundwater hydrogeochemistry.

关键词： Arsenic Fluorescence spectroscopy Organic matter characterization Parallel factor analysis (PARAFAC) Groundwater quality

多晶la_(0.49)Sr_(0.51)MnO_3中的铁磁反共振

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深圳大学学报（理工版） 2006年第4期23卷 314-319页

作者：舒启清柳文军 Bhagat S M Lofland S e Troyanchuk I O 深圳大学材料学院深圳市特种功能材料重点实验室深圳518060 马里兰大学物理系白俄罗斯科学院固体物理研究所

采用谐振腔微扰技术测量了多晶la_(0.49)Sr_(0.51)MnO_3的微波吸收(PMA),观察到在居里温度TC或奈尔温度TN附近发生PMA呈现极小值即铁磁反共振(FMAR)现象.基于朗道-利弗希茨-吉尔伯特模型,磁化强度μ0M对温度的依赖关系可以从FMAR得到.... 详细信息

采用谐振腔微扰技术测量了多晶la_(0.49)Sr_(0.51)MnO_3的微波吸收(PMA),观察到在居里温度TC或奈尔温度TN附近发生PMA呈现极小值即铁磁反共振(FMAR)现象.基于朗道-利弗希茨-吉尔伯特模型,磁化强度μ0M对温度的依赖关系可以从FMAR得到.发现当外加直流磁场μ0H=0时,不同微波频率下得到的磁化强度μ0M对温度的依赖关系与标度律符合.然而,当μ0H≠0且μ0Hla_(0.49)Sr_(0.51)MnO_3是一种由铁磁(FM)和反铁磁(AFM)等多态微区组成的密切合物,是一个包含多个状态和取向互不相同的畴壁的复杂系统;②在μ0H增强或温度下降的过程中,都存在导致PMA增加或减少的两种机制的竞争.

关键词：多晶la0.49Sr0.51MnO3 微波吸收铁磁反共振标度律密切合物

A systematic study on the role of SentiWordNet in opinion mining

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Frontiers of Computer Science 2021年第4期15卷 165-183页

作者： Mujtaba HUSNAIN Malik Muhammad Saad MISSeN Nadeem AKHTAR Mickael COUSTATY Shahzad MUMTAZ V.B.Surya PRASATH Department of IT Faculty of ComputingThe Islamia University of BahawalpurBahawalpur 63100Pakistan laboratoire Informatique Image et Interaction(L3i)Facultés des Sciences et TechnologiesUniversity of La RochelleLa Rochelle 17000France Division of Biomedical Informatics Cincinnati Children’s Hospital Medical CenterCincinnati 45229USA Department of Pediatrics University of Cincinnati College of MedicineCincinnati 45229USA Department of Biomedical Informatics College of MedicineUniversity of CincinnatiCincinnati 45267USA Department of electrical engineering and Computer Science University of CincinnatiCincinnati 45221USA

Sentiment lexicons(SL)(aka lexical resources)are the repositories of one or several dictionaries that consist of known and precompiled sentiment *** lexicons play an important role in performing several different opinion mining *** efficacy of the lexicon-based approaches in performing opinion mining(om)tasks solely depends on selecting an appropriate opinion lexicon to analyze the ***,one has to explore the available sentiment lexicons and then select the most suitable *** available resources,SentiWordNet(SWN)is the most widely used lexicon to perform tasks related to opinion *** SWN,each synset of WordNet is being assigned the three sentiment numerical scores;positive,negative and objective that are calculated using by a set of *** this paper,a detailed and comprehensive review of the work related to opinion mining using Senti-WordNet is provided in a very distinctive *** survey will be useful for the researchers contributing to the field of opinion *** features make our contribution worthwhile and unique among the reviews of similar kind:(i)our review classifies the existing literature with respect to opinion mining tasks and subtasks(ii)it covers a very different outlook of the opinion mining field by providing in-depth discussions of the existing works at different granularity levels(word,sentences,document,aspect,clause,and concept levels)(iii)this state-ofart review covers each article in the following dimensions:the designated task performed,granularity level of the task completed,results obtained,and feature dimensions,and(iv)lastly it concludes the summary of the related articles according to the granularity levels,publishing years,related tasks(or subtasks),and types of classifiers *** the end,major challenges and tasks related to lexicon-based approaches towards opinion mining are also discussed.

关键词： opinion mining lexical based resources Senti-WordNet opinion strength